Benzyl Bromide → Ethyl 1,2,3,4-tetrahydro-2-methyl-1-oxo-8-(phenylmethoxy)pyrrolo[1,2-a]pyrazine-7-carboxylate

To a solution of ethyl 8-hydroxy-2-methyl-1-oxo-1,2,3,4-tetrahydro-pyrrolo[1,2-a]-pyrazine-7-carboxylate (25.0 g, 104.9 mmol) in DMF (500 mL), potassium carbonate (58 g, 420 mmol) and benzyl bromide (14.9 mL, 126 mmol) was added. The reaction mixture was stirred at rt over night. The mixture was filtered and the filtrate concentrated under vacuum. The residue was partitioned between dichloromethane and brine. The organic extract was washed with brine, dried over sodium sulfate, filtered, and concentrated under vacuum. The residue was subjected to column chromatography on silica gel eluted with ethyl acetate to give titled material.